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2003 Miklós Schweitzer
7
7
Part of
2003 Miklós Schweitzer
Problems
(1)
Miklós Schweitzer 2003, Problem 7
Source: Miklós Schweitzer 2003
7/30/2016
Let
r
r
r
be a nonnegative continuous function on the real line. Show that there exists a function
f
∈
C
1
(
R
)
f\in C^1(\mathbb{R})
f
∈
C
1
(
R
)
, not identically zero, such that
f
′
(
x
)
=
f
(
x
−
r
(
f
(
x
)
)
)
f'(x)=f(x-r(f(x)))
f
′
(
x
)
=
f
(
x
−
r
(
f
(
x
)))
,
x
∈
R
x\in\mathbb{R}
x
∈
R
.(translated by L. Erdős)
college contests
Miklos Schweitzer
function